The Key Technology Research Of The 3D Mesh Compression AND The Mesh Traksmission Over Unreliable Network

As one of the most common representation methods of the virtual surface and volumes,3D grid is widely used in the field of the three dimensional applications. While with the development of the network applications and the improvement of the details of 3D models, the raw data amount of the 3D grid is constantly improving. When faced with the unreliable network, concerning the packets loss problem that the huge raw data amount and the limited network bandwidth lead to, how to reduce the data amount of 3D grids and handle the packets loss problem are the two topics we will talk in this article.Mesh compression is one of the best solutions for the first problem. Mesh compression has become a hot topic since the 1990s, especially the single-rate mesh compression and the progressive mesh compression. Nowadays many extension research fields including the dynamic mesh compression, the randomly accessible mesh compression and the out-of-core mesh compression of the large scale meshes are still hot areas of the research. In recent years, the research about the single-rate mesh compression decreases, most related researches are only about one or two parts of the mesh compression. We believe that in the research field of the single-rate mesh compression, the compression efficiency can still be improved, in other words, there are still potentions and necessities in the research field of single-rate mesh compression.In this paper, we introduce several classical mesh compression algorithms first. Then we propose our innovative topology traversing method which belongs to the single-rate triangular mesh compression. The main procedure consists of the concentric layered decomposition of the mesh, the construction of the spanning tree structure,the topological traversing method, the process of the vertex split and edge split, the decoding method and so on. We also propose a local cylindrical coordinates based geometry prediction method. We introduce the encoding method, the decoding methodand the experiments in details. According to the data the experiments show, we believe that by using this mesh compression method, we can gain a better compression rate with a little distortion.Meanwhile, in order to handle the mesh transmission problem over the unreliable network, we believe that our spanning tree structure can easily handle the re-transmitting problem for the server side as well as the re-requesting problem and reconstructing problem for the client side. We design three different transmitting strategies, conduct a lot of comparative experiments under the unreliable network circumstance and analyze the comparative results.